Closure for a bottle or the like

ABSTRACT

A closure for the bottle having a cap-like closure part with an inward projection at its edge for clasping an outward projection on the neck of the bottle or the like. In the area of the face edge of the bottle neck the interior of the closure has a sealing surface for seating on the end face of a bottle neck. The sealing surface (5) has a sealing surface part (8) which is formed on the radial inner side of a projection directed away from the base of the closure part axially and clasping around the bottle neck and which is sloped radially toward the interior and axially counter to the screwing direction. The sloping sealing surface part (8) ensures the centering of the seal, improves the sealing effect, and contributes to the opening of the overpressure valve thereby formed, the opening pressure of which can be influenced through the selection of the degree of slope of the sealing surface part (8).

BACKGROUND OF THE INVENTION

1. Field of the Invention

The invention concerns a closure, for a bottle or the like.

2. Description of Related Art

A closure for a bottle or the like is known from DE 42 34 010 A1 whichhas a cap-like closure part having a backward-facing projection on itsedge for clasping an outward-directed projection on the neck of a bottleor the like and which has a sealing surface on its interior in the areaof the edge of the face of the neck of the bottle. This sealing surfaceis situated on a seal, arranged at the base area of the closure part,which has a recess on the side directed toward the base of the cap-likeclosure part. This recess extends from a radial area on the inside ofthe contact surface of the seal radially outward toward the edge of theface of the neck of a bottle. The sealing surface for seating on theface edge of a bottle neck is located on the side of the seal away fromthe base of the cap-like closure, whereby the seal has a projection,away from the base of the closure part, along its outer edge. Thisprojection clasps around the outside of the bottle neck in the axialdirection.

The recess in the seal on the side toward the base of the closure partmakes it possible for the seal to lift from the face surface of a bottleneck in the event of overpressure so that there is a release of pressureand the bursting of the bottle is avoided. Outside of the recess, suchlifting cannot take place, and since the material of the seal iscompressible with respect to volume, these areas of the seal form a seatfor the closure, which is important in particular in the case of a screwclosure. By this means, defined compression forces are produced in thearea of the seal where the recess is located. Thus the pressure at whichthe seal lifts from the bottle neck in the area of the recess isprecisely defined independent of the magnitude of the force with whichit is screwed on. Movements of the base area of the cap-like closurethrough arching upward as a result increases in pressure are not used inthis closure.

In order to improve the seating effect of the seal in the case of thisknown closure, this seal has a ring-shaped area in which no compressionof the seal can take place. This ring-shaped area is naturally in thearea of the face edge of a bottle neck. Since this area is radially verysmall, it is difficult in practice to assure that the ring-shaped areaseats on the bottle neck. As a result of this ring-shaped seating area,the area in which the seal can fit and can lift in the event ofoverpressure is very small. In practice, this results in sealingproblems.

The task of the invention is to create a closure of the type indicatedin the introductory clause of the claim in which the disadvantages ofthe known closure are avoided, i.e., in which in particular the sealeffect is improved with relatively large tolerances of width of the faceedge of a bottle neck and of the radial position of the same.

The task of this invention is solved through the principle indicated inthe characteristic of the claim.

BRIEF SUMMARY OF THE INVENTION

The basic idea of this principle consists of creating a sloping,essentially cone-shaped sealing surface on the seal, which forms atleast a part of the seal surface and which causes a centering of theseal and an improvement of the sealing effect. This is a result of thesloping surface seating at the outer border of the face edge of a bottleneck and causing an elevated surface compression there. This compressionis reduced or eliminated if the base of the closure part arches outwardupon overpressure, thereby creating the effect of an overpressure valve.

It is also advantageous for the sealing surface part to extend out overthe outer border of the face surface of a bottle neck, whereby theblow-by pressure can be influenced by means of the dimensioning of theradial overhang. A relatively small overhang results in a small blow-bypressure, and relatively greater overhang in a larger blow-by pressure.

The angle of slope of the sealing surface part is advantageouslyselected such that its movement away from the edge of a bottle neck isgreatest upon the arching of the base of the cap-like closure part.Through the degree of slope, it is possible to influence in anadvantageous manner the pressure above which the sealing effect isreduced or disappears completely and thus the blowing off ofoverpressure occurs.

The radial elongation of the sloping sealing surface portionadvantageously extends at least over the tolerance range of the radiallyouter border of the face surface of the neck of a bottle. By this means,the function of the sloped sealing surface portion is assured for alloccurring radial dimensions of the outer border of the face surface of abottle neck of bottles which are to be closed by the closure.

The sealing surface portion and the projection are advantageouslyprovided on a seal arranged in the base of the cap-like closure part.The material of this seal can then be selected independent of that ofthe cap-like closure and thus can be adapted to the sealing conditions.

With the use of such a separate seal it is advantageous for it to have,on the side toward the base, at least one recess which extends from aradial area inside of the face surface of a bottle neck radially outwardfrom the bottle. It is advantageous for the recess to extend into theouter surface of the projection. In the area of the recess, the seal canyield so that it can withdraw in the event of an overpressure and cansupport the blow-by process in the event of overpressure.

BRIEF DESCRIPTION OF THE DRAWING

With the aid the drawing, the invention is explained in greater detailbased on an embodiment example.

FIG. 1 is a half radial section through an embodiment example of theinvention.

FIG. 2 in a plan view of the seal per FIG. 1.

DETAILED DESCRIPTION OF THE PRESENT INVENTION

The closure presented in FIG. 1 halved and sectioned shows a cap-likeclosure part 1, the edge 2 of which is depicted only partially and whichhas, in the part not depicted, an inward-directed projection, such as byway of example a crimp of a crown or a thread of a metal or plasticscrew closure, for clasping an outward-directed projection on the bottleneck. Opposite a base 3 of the closure part 1, a seal 4 is arrangedwhich has a sealing surface 5 for seating on the face edge of a bottleneck.

The seal 4 has, along its outside edge, a projection 6 directed awayfrom the base 3 of the closure part 1, which projection clasps aroundthe outer edge of the bottle neck when screwed on. The projection 6 hasa small extension 7 which engages toward the inside in a complementarygroove in the edge 2 of the closure part 1 so that the seal 4 issecurely united with the closure part 1.

The sealing surface 5 has a sealing surface part 8 on a radial innersurface of the projection 6. This sealing surface part slopes from theprojection 6 toward the interior. This sloping, therefore cone-like,sealing surface part 8 of the projection 6, in screwed-on state, isseated firmly on the outer edge of the face surface of a bottle neck,thereby forming a good seal. Upon an increase of pressure in the bottle,the base 3 arches outward, causing the edge 2 in the area of sealingsurface part 8 to move away from the face edge of the bottle upward andoutward approximately perpendicular to itself, thus reducing oreliminating the sealing effect allowing overpressure to escape. Thedegree of slope of the sealing surface 3 determines in part the openingpressure of the overpressure valve formed by the closure.

On the side away from the sealing surface 5 and the sloping sealingsurface part 8 and toward the base 3 of the closure part, the seal 4 hasnarrow radial channels 9. In the area of these channels 9, the seal 4can yield toward the base 3 of the closure part 1 if the pressure issufficiently high in the bottle.

By these means, an overpressure valve is formed which can be dimensionedsuch that bursting of a bottle is avoided.

In the embodiment example depicted, the channels 9 extend into the outersurface of the projection 6 so that the material of the projection canalso yield, specifically in a radial direction toward the outside, ifthere is sufficiently high pressure.

FIG. 2 shows only a portion of the seal per FIG. 1, specifically fromabove in the drawing of FIG. 1, i.e., from the base 3 of the closurepart 1. In this manner, the size and the course of the channels areclearly visible.

While we have shown a presently preferred embodiment of the presentinvention, it will be apparent to persons skilled in the art that theinvention may be otherwise embodied within the scope of the followingclaims.

We claim:
 1. A closure for a bottle having a neck with a face surfaceand a face edge thereon, said closure including a cap-like closure partwhich has, an edge, an inward-directed projection on said edge forclasping an outward-directed projection on the neck of the bottle and onthe interior, in the area of the face edge of the bottle neck, a sealingsurface for seating on the face surface of the bottle neck,characterized by the fact that the cap-like closure part has a base andthe sealing surface (5) has a cone like sealing surface part (8) whichis formed on the radial interior side of a projection directed axiallyaway from the base (3) of the closure part (1), said sealing surfacepart clasping around the outside of the bottle neck and sloping radiallyto the inside and axially counter to the screwing direction.
 2. Aclosure in accordance with claim 1 characterized by the fact that theslope of the sealing surface part (8) is selected such that its movementaway from the edge of a bottle neck is greatest in the event ofelevation of pressure and arching of the base (3) of the cap-likeclosure part (1).
 3. A closure in accordance with claim 1 or 2characterized by the fact that the slope of the sealing surface part (8)is dimensioned dependent upon the opening pressure, such that theopening pressure is lower with a smaller slope and greater with a largerslope.
 4. A closure in accordance with claim 1 or 2 characterized by thefact that the sealing surface part (8) extends out over the exteriorborder of the face surface of the bottle neck, whereby the radialoverhang is dimensioned dependent on the desired blow-by pressure suchthat the opening pressure is lower with a smaller overhang and greaterwith a larger overhang.
 5. A closure in accordance with claim 1 or 2characterized by the fact that the radial extension of the slopedsealing surface part (8) extends at least over the tolerance range ofthe radial exterior border of the face surface of the neck of thebottle.
 6. A closure in accordance with claim 1 characterized by thefact that the sealing surface part (8) and the projection (6) areprovided on a seal (4) arranged in the flow of the cap-like closure part(1).
 7. A closure in accordance with claim 6 characterized by the factthat the seal (4) has, on its side directed toward its base (3), atleast one recess (9) which extends from a radial area inside of the facesurface of a bottle radially outward from the bottle.
 8. A closure inaccordance with claim 7 characterized by the fact that the recess (9)extends to the outer surface of the projection (6).